Zigzag mechanisms for sewing machines



May 31, 1966 A. F. DAMICO 3,253,559

ZIGZAG MECHANISMS FOR SEWING MACHINES Filed Dec. 5, 1955 6 Sheets-Sheet l INVENTOR. Anthony F. 0341mm BY WITNESS W7 @M\ W ATTORNEY A. F. DAMICO May 31, 1966 ZIGZAG MECHANISMS FOR SEWING MACHINES 6 Sheets-Sheet 2 Filed Dec. 5, 1955 INVENTOR. 14 D f/lmico Antho ATTORNEY 6 Sheets-Sheet 5 Filed Dec. 5 1955 M N 5 9 ml w 9 9 n 5 "m6 w n 76 2Q L 7 WM... 9 a. 9 .H a 7 m 6 0 w 2. i w 3 W 4 6 5 m 6 6-. 7r 6 3, 9 In 3 Q 5 m fl V -1..- 9 88 h m WM. m am A w 5% 5 7 5 3 E. H u 2 J0 o g F.

F i 6 INVENTOR.

BY Anthony EDi/lmico 41.4

ATTORNEY y 1, 1966 A. F. DAMICO 3,253,559

ZIGZAG MECHANISMS FOR SEWING MACHINES Filed Dec. 5, 1955 6 Sheets-Sheet 5 m INVENTOR. Anthony E DZlmico WITNESS I62 I60 630 I59 9 y 1966 A. F. D'AMICO 3,253,559

ZIGZAG MECHANISMS FOR SEWING MACHINES Filed Dec. 5 1955 6 Sheets-Sheet 6 I I/IIIIIIIIIIII Fig. '8. INVENTOR.

Anthony E Dilmico BY United States Patent 3,253,559 ZIGZAG MEtIHANlSMS FUR SEWING MACHENEE; Anthony F. DAmico, South Norwalir, (Iona, assignor to The Singer Company, New York, N.Y., a corporation of New Jersey Filed Dec. 5, 1955, Ser. No. 551,091) 7 (Ilaims. (Cl. 112-158) The present invention relates to sewing machines and has for a primary object to provide an improved zigzag mechanism therefor.

More specifically it is an object of this invention to provide an improved construction and arrangement for a cam-controlled zigzag mechanism which will efficiently accommodate a large number of pattern cams without detracting from the design of the machine, whereby an increased variety of stitch patterns can be automatically produced by the sewing machine.

It is also an object of this invention to provide, in a cam-controlled zigzag sewing machine, a new and improved cam follower means which is particularly useful in conjunction with a machine having stitch pattern cams mounted in axial'alignment with the main-shaft of the machine.

It is a further object of this invention to provide in a pattern cam controlled zigzag mechanism, a readily replaceable special cam that can be used for producing stitch patterns not provided for by the regular stack of cams.

It is a further object of this invention to provide means for mounting a stack of pattern cams whereby it can be readily removed and replaced by a different set of cams for producing other stitch patterns.

It is a further object of this invention to provide an improvement in the means for effecting adjustment of the vibration or bight control of a zigzag sewing machine, whereby an adjustment of the control mechanism will not vary the center line or null point of the stitch pattern.

Having in mind the above and other objects that will be evident from an understanding of this disclosure, the invention comprises the devices, combinations and arrangements of parts as illustrated in the presently preferred embodiment of the invention which is hereinafter set forth in such detail as to enable those skilled in the art readily to understand the function, operation, construction and advantages of it when read in conjunction with the accompanying drawings in which:

FIG. 1 is a front elevation view of that portion above the bed of a sewing machine embodying the present invention, in which view the cover plates for the cams and adjacent mechanisms have been removed.

FIG. 2 is a fragmentary rear elevation view of the sewing machine illustrated in FIG. 1 in which the cover plate at the juncture of the standard and bracketarm has been removed.

FIG. 3 is a fragmentary top plan view of the sewing machine illustrated in FIG. 1 with the bracket-arm cover plate removed and the bed outline not shown.

FIG. 4 is a fragmentary front elevation view of a por tion of the bracket arm with the cam cover plate in place.

FIGS. 5 and 6 are detail sectional views taken substantially on the lines 5-5 and 6-6, respectively, of FIG. 3.

FIG. 7 is a detail sectional view taken substantially on the line 7-7 of FIG. 6, with the hand-knob removed.

FIGS. 8 and 9 are detail sectional views taken substantially on the lines 8-8 and 9-9, respectively, of FIG. 1.

FIG. 10 is a detailed sectional view taken substantially on the line 10-10 of FIG. 8.

FIG. 11 is a fragmentary detail sectional view taken substantially 0n the line 11-11 of FIG. 8.

FIG. 12 is a detail sectional view illustrating a modification of the needle-position control means.

ice

FIG. 13 is a fragmentary top plan view similar to FIG.

3 but illustrating a modified form of the present invention.

FIG. 14 is a fragmentary front elevation view of the modification illustrated in FIG. 13.

FIG. 15 is a fragmentary sectional view taken substantially on the line 15-15 of FIG. 14.

FIG. 16 is a fragmentary sectional view taken substantially on the line 16-16 of FIG. 13.

FIG. 17 is a fragmentary rear elevational view on an enlarged scale of the modification of the invention illustrated in FIG. 13.

FIG. 18 is a fragmentary sectional view taken substantially on the line 18-18 of FIG. 14.

FIGS. 19, and 21 are detail sectional views taken substantially on the lines 19-19, 20-20 and 21-21 of FIG. 13, respectively.

The sewing machine to which the present invention has been applied is similar to that disclosed in the application of Perla et al., Ser. No. 386,684, filed October 19, 1953, and includes a frame having a bed-plate 1, a standard 2 rising from one end of the bed-plate and carrying a bracket-arm 3 that terminates in a head 4 overhanging the bed-plate 1. A cover plate 5 is provided for closing the upper portion of the bracket-arm 3. Since the present improvement is directed to the needle-jogging mechanism of the machine, the various other mechanisms have been illustrated only insofar as believed necessary for a complete understanding of the invention. It will be understood that the mechanisms not herein described may be of any conventional construction, such as disclosed in the above Perla et al. application and the patents referred to therein.

Journaled longitudinally of the bracket-arm 3 is a mainshaft 6 that extends through the end wall of the frame at the standard 2 to receive a belt-pulley 7 about which a belt (not shown) is adapted to be entrained for the purpose of delivering power to the machine. As seen in FIG. 2, the shaft 6 is provided in the head 4 with the usual counter-balanced crank 8 which is connected by a universal link 9 to a needle-bar 10 for imparting longitudinal reciprocation to the needle-bar upon rotation of the shaft 6. The needle-bar 10 is journaled for longitudinal reciprocation in a vibratory gate 11 that is hung on a pivot screw 12 carried by a supporting element 13 screwed into the upper portion of the head 4. The gate 11 provides for lateral vibration of the needle-bar during sewing in order to form ornamental zigzag stitches. Vibration about the pivot 12 is imparted to the needle-bar 10 through an arm 14 having at its free end a pivot block 15 which is embraced by the worked end of a crank-arm 16. The crankarm 16 is secured to a shaft 17 journaled in the head 4 on an axis parallel to the axis of the pivot 12. At the rear of the head 4, the shaft 17 has secured thereto a second crank-arm 18 which is pivotally connected at 26) to one end of a pitman 19. With the above mechanism, which is of conventional construction, actuation imparted to the pitman 19 will effect swinging of the needle-bar 10 about the pivot 12 laterally of the line of'feed of the machine. 4

The pitman 19, which is disposed externally of the bracket-arm 3 at the rear thereof, is pivotally connected at the end opposite the pivot 28 to a reduced eccentric end portion 21 of a pin 22 (see FIG. 8) that is carried by a slide block23 mounted for sliding movement on a pair of guide pins 24. The pins 24 are mounted at each end in the spaced lugs 25 of an actuating element or carrier 26 that is pivotally secured by the screw 27 to one arm of a bell-crank 29 which is in turn pivoted on a needle-position control shaft 30 journaled in the standard 2 from the front to the back thereof. The carrier 26 is frictionally held against pivotal movement relative to the bell-crank 29 about the pivot screw 27, and to this ?atented May 31, 1966 end the lower end of the enlarged hub of the bell-crank 29 is turned upwardly to provide a lip 31 to embrace the outer face of the depending lower end 32 of the carrier 26. To increase the friction generated, there is provided a spring-pressed plunger 33 which urges the outer face of the lower end 32 of the carrier into contact with the inner face of the lip 31. There is provided a slot-like recess 34 in the rear face of the lower end 32 of the carrier 26 that is disposed to receive the plunger 33 when the carrier 26 is adjusted in its normal position relative to the bellcrank 29. This not only serves to indicate when the carrier 26 is in its normal position but also assists the frictional forces holding the carrier in this position.

The bell crank 29 includes a second arm 35 (see FIG. which is connected to the cam-controlled actuating mechanism as hereinafter described, whereby the bellcrank 29 is oscillated about the shaft 30. It will be understood that oscillation of the bell-crank 29 will effect corresponding oscillation of the carrier 26 which, through the slideblock 23, oscillates the pin 22 about the axis of the shaft 30, and this in turn actuates the pitman 19 to vibrate the needle-bar 19. The amount of vibration imparted to the needle-bar 10 is dependent upon the position of the pin 22 radially with respect to its center of oscillation, which is the axis of the shaft 30. The greater the spacing between the axis of the pin 22 and shaft 30, the greater will be the amplitude of needle-bar vibration. In the position shown in the drawings, the pin 22 and shaft are axially aligned so that none of the oscillation of the bell-crank 29 will be transmitted to the needle-bar 10.

The position of the pin 22 radially with respect to its center of oscillation, which is the shaft 30, is varied by moving the slide block 23 on the guide pins 24. To this end there is provided a vibration or bight control mechanism including a connecting link 36 which is at one end pivotally mounted together with the pitman 19 on the eccentric end portion 21 of the pin 22. The pitman 19 and link 36 are held on the reduced eccentric end 21 of the pin 22 by a locking screw 37. The other end of the connecting link 36 is pivotally connected by a pivot screw 38 to the free end of a crank-arm 39 that is secured to the rear end of a vibration control shaft 40 journaled in the standard 2 parallel to the right-left control shaft 30. At the front of the machine, the shaft 40 is provided with a finger piece or control knob 41 having a thumb screw 42 adapted to secure the same in any adjusted position.

The needle-position control mechanism comprises an eccentrically located stud 43 (see FIGS. 8 and 10) mounted upon the end of the shaft 30 with the axis thereof parallel to the axis of the shaft 30. The free end of the stud 43 is disposed in a slot 44 in the rear face of the carrier 26, the slot 44 being formed by two spaced lugs 45 on the carrier 26. At the front of the machine, the shaft 30 is provided with a control knob 46. When the shaft 30 is manually rotated by means of the knob 46, the eccentric stud 43 acting in the slot 44 will shift the carrier 26 relative to the bell-crank 29 about the pivot screw 27, thereby varying the null point of the zigzag pattern between the positions of maximum throw at the right and left of the pattern. As above noted, the spring-pressed detent 33 in the hub of the bell-crank 29 cooperates with the recess 34 in the carrier 26 and thereby, together with the frictional forces, releasably hold the carrier 26 in its normal position relatively to the bellcrank 29, which is that position in which the null point is in the center of the stitching pattern. The right and left positions of the null point are adjustably determined by a pair of stop screws 47 which extend through the portion of the lip 31 of the bellcrank 29 that underhangs the bottom edge of the carrier 26. The screws 47 provide for adjustment of the right and left positions of the null point and can be locked in the adjusted position by means of the nuts 48.

As the vibration control mechanism is moved to increase or decrease the amplitude of vibration imparted to the needle-bar 10, the pin 22 is moved by the slide 23 on a straight line defined by the guide pins 24. If the stitching pattern is to be about a common null-point or centerline, it would of course be necessary that the pivot 20 remain stationary during adjustment of the vibration control mechanism and to accomplish this the pitman 19 must move in an are about the pivot 20. To compensate for the differences between the straight-line motion of the end pitman 19 and the desired arcuate motion, there has been provided a compensating mechanism comprising a pair of studs 49 (see FIG. 10) which cooperate with radial slots 50 extending inwardly from the periphery of a flange 51 at the inner end of the pin 22. As the slide block 23 is moved along the guide pins 24, the studs 49 will mesh with the slots 59 in a gear-like fashion to rotate the flange 51 and thereby rotate the pin 22. Rotation of the pin 22 with its eccentric end portion 21, will effect an adjustment of the position of the end of the pitman 19 so that the movement thereof, instead of being in a straight-line as determined by the guide-pins 24, will be in an are about the pivot 20.

The actuating mechanism for oscillating the bell-crank 29 about the needle-control shaft 30, and thereby imparting zigzag vibrations to the needle-bar, includes a universal link 52 connected at one end to the free end of the arm 35 of the bell crank 29 and connected at the other end to the end of a crank arm 53 which is secured to a pivot shaft 54 arranged parallel to the main shaft 6 and journaled for oscillation in a pair of lugs 55 and 56 (FIG. 1) depending from the cover-plate 5. The shaft 54 has mounted thereon a cam follower 57 having an integral hub 58. The hub 58 is free to slide on the shaft 54 but is keyed thereto for oscillation by means of a key 60 which is slidably seated in a keyway 61 in the shaft 54. The hub 58 is adapted to be slid along the shaft 54 to place the cam follower 57 into engaging relation with any one of the individual cams 63 which are mounted upon and keyed to a three-piece cam shaft 64 arranged with the axis thereof parallel to that of the main shaft 6 and journaled in lugs 65, 66 and 67 (FIG. 3) at the front of the bracket arm 3. The cam follower 57 is resiliently urged into contact with the periphery of the selected one of the cams 63 by a coil tension spring 68 (FIG. 2) which is secured at one end to the arm 35 of the bell crank 29 and at the other end to a pin 69 secured to the machine frame. The spring 68, acting through the link 52 and the crank arm 53 biases the shaft 54 in that direction in which the free end of the cam follower 57 rides on the periphery of the selected cam 63. As herein illustrated, the bank of cams is made up of twenty-four of the earns 63. However, it will be understood that this invention is not limited to this number of cams but may be used with even a greater number of cams depending upon the size of the bracket-arm 3.

Rotation is imparted to the cam shaft 64 by a gear connection with the main shaft 6 (FIG. 9) which gear connection comprises a worm 70 on the shaft 6 meshing with a worm wheel 71 mounted upon a countershaft 72 journaled transversely of the bracket-arm 3, and a helical gear 73 mounted upon the countershaft 72 and meshing with a similar gear 73a on the shaft 64. Thus, upon rotation of the main shaft 6, rotation will be imparted to the cam shaft 64 and the earns 63 which, through the cam follower 57, will impart vibration to the needle-bar in accordance with the designed pattern of the selected cam 63 upon which the cam follower 57 is riding.

The cam-selecting mechanism comprises a selector lever 74 loosely journaled on the hub 58 of the cam follower and held thereon by a retaining ring 75. The selector lever 74 extends through a slot 76 in a cover plate 77 that is secured to the top cover plate 5 of the machine by screws 78. At its free end, the selector lever 74 carries a finger-piece 79 that is screwed onto a vertically disposed extension thereof and is formed with an indicator or pointer 30. A plurality of slots 81 are formed in the cover plate 77, each corresponding to one of the cams 63 so that the selector lever 74 may be readily positioned and held with the cam follower 57 on the corresponding cam 63. The free end of the selector lever 74 is biased downwardly into the slots 81 by a leaf spring 82 (FIG. 8) which is secured to the lever 74 by screws 83 and acts against a ridge 84 depending from the cover plate 5. There is a stud 85 extending laterally from the cam follower arm 57 that normally overhangs a lip 06 formed on the lever 74. In order to move the cam follower 57 from the periphery of one of the cams 63 to that of another, the finger piece 79 is pushed against the action of the spring 82 to rotate the lever 74 about the hub 58 of the cam follower 57. The lever 74 is thereby lifted out of the slot 81 in which it is then positioned, and at the same time, the lip 86 of the selector lever 74 contacts the stud 85 on the cam follower 57 to lift the same from the periphery of the cam 63 against the action of the spring 68 to a point that is higher than the highest high-point of the cams 63. The cam follower 57 is now free to move across the cams 63 into a position in which it will cooperate with a different one of them. This motion is accomplished by pushing the finger piece 79 in the desired direction, thus moving the hub 58 of the cam follower 57 and the cam follower along the pivot shaft 54. When the cam follower 57 is properly adjusted relatively to the newly-selected cam 63, the lever 74 will .move into the corresponding slot 31 under the action of the spring 82 When the finger piece is released.

To facilitate the selection of the desired one of the cams 63, suitable indicia 87 (FIG. 4) which illustrates the stitch pattern of the respective cams, is provided in position to cooperate with the pointer 80 of the selector lever 74. The indicia 87 is provided on a sheet metal cam cover-plate 88 that is designed to enclose the cams 63 and which is releasably secured in place by means of a tongue 89 at its upper edge that engages in a cooperating aperture in the cover plate 77. Along its side edges, the cover plate 88 is adapted to snap over lugs 90 (FIG. 4) cast on cover plates 91'and 92 which enclose the mechanism at each end of the cam shaft 64. The cover plate 91 is secured to the bearing lugs 66 and 67 for the shaft 64 by screws 93 (FIGS. 3 land 4) and the cover plate 92 is secured to the bearing lug 65 by a screw 94.

As hereinbefore mentioned, the cam shaft 64 is formed in three parts. 95 (FIG. 1) journaled in the bearing lugs 66 and 67 and having mounted thereon the gear 73a and a cam-supporting shaft 96 which is journaled at one end in the bearing lug 66 and at the other end is supported by the third part of the shaft 64 as later described. Adjacent the lug 66 the shaft 96 is provided with a tongue 97 (FIGS. 1 and 7) which mates with a corresponding groove in the shaft 95 to lock the two together for rotation. The cams 63 are stacked on the shaft 96 and clamped thereon between a collar 98 at the one end thereof and a nut 99 threaded onto the other end. The cams 63 are keyed to the shaft 96 for rotation therewith by means of a key 100 fitted in a slot 101 (FIG. 6) in the shaft 96 and engaging in a keyway 102 formed in each of the cams 63.

The third part ofthe shaft 64 is an endwise shiftable shaft 103 having a cylindrical recess formed in the end thereof to receive a reduced end portion 104 of the shaft 96 to support the same and a tongue 105 to lock the shafts .96 and 103 together for rotation. The shaft 103 is mounted for endwise sliding movement in a sleeve 106 and is locked to the sleeve for rotation by a key 107 carried by the shaft103 and fitted in a keyway 108 in the sleeve. The sleeve 106 is journaled for rotation in the bearing lug 65 and is held against excessive endwise play relatively to the bearing lug 65 by a flange 109 on the sleeve disposed on one side of the bearing and a pair of nuts 110 on the other side which may be locked in adjusted position. The shaft 103 is held in its normal operative position by a spring-pressed plunger 111 carried by the shaft 103 and adapted to engage in a recess in the sleeve 106. The shaft 103 is provided with a reduced end 112 These three parts include a drive shaft' that extends through the end of the sleeve 106, the end 113 of which is also reduced to conform to the reduced end 112 of the shaft 103. A screw 114 is threaded into an axial bore in the reduced end 112 of the shaft 103 and a lock nut 115 is threaded thereon. The head of the nut 115 is larger in diameter than the reduced end 112 of the shaft 103 and therefore serves as a stop for adjustably limiting the axial sliding movement of the shaft 103 relatively to the sleeve 106 in the one direction. This sliding movement is limited to the position in which the plunger 111 is seated in the cooperating recess in the sleeve 106v Mounted upon the reduced end 113 of the sleeve 106 is a cam 116, hereinafter more fully described, that is similar to the cams 63 and which is held on the end 113 by an internally threaded hand-nut 117. The nut 117 is threaded onto the shaft-end 113. The cam 116 is locked to the sleeve 106 for rotation therewith by a stud 118 on the flange 109 of the sleeve 106, which stud extends through a slot 119 in the cam 116. The hand-nut 117 also serves to limit a-xial movement of the shaft 103 in the direction opposite to that direction of motion limited by the nut 115, thus positively locking the assembly together.

The above construction is designed to permit removing the stack of cams 63. The cam assembly is designated by the numeral 120, and comprises the cams 63 stacked on the shaft 96 and held thereon by the collar 98 and nut 99. To remove the cam assembly 120 the hand nut 117 is removed, after which the assembly 120 can be shifted to the left as seen in FIGS. 1, 3, 6 and 7 as the shaft 103 is also. moved to the left within the sleeve 106. When the right hand end of the shaft 96 is free of the bearing lug 66, the assembly 120 can be readily removed for repairing worn or damaged ones of the cams 63 or substituting other cams with different patterns, or substituting a whole new assembly. When a different cam or a different assembly is substituted, corresponding changes should be made in the indicia 87. To replace the assembly 120, it is aligned with the shafts 95 and 103 and then the shaft 103 is pushed to the right until the plunger 111 snaps into the cooperating recess in the sleeve 106. The hand-nut 117 is then replaced to lock the assembly.

The earns 63 would ordinarily be adequate to provide all the desired stitch patterns. However it is still desirable to provide means for accommodating a readily replaceable special cam which may be used for sewing a particular stitch pattern that is-not included among the patterns of the earns 63. The special cam in the present case is the cam 116 which can be removed and replaced merely by removing the hand-nut 117. A separate follower mechanism is provided for the cam 116 which comprises a cam follower 121 having a hub 122 (FIGS. 3 and 11) loosely mounted on the pivot shaft 54, and held thereon by a retaining ring 123, the hub 122 having a reduced portion 124 extending through the bearing lug 55 and having axially directed slots 125 formed therein. Tongues 126 complemental to the slots 125 are formed on the face of the hub 58 of cam follower 57 which tongues 126 enter the slots 125 when the follower 57 is moved to its extreme left-hand position to key the follower 121 to the pivot shaft 54.

The follower 121 is held out of contact with the cam 116, to prevent undue wear of the cam 116 when it is not in use, by means of a plunger 127 (FIGS. 3 and 5) extending through a bore in a boss 128 on the bearing lug 55 for the pivot shaft 54. The plunger 127 has an axially-moving radial displacement cam 129 upon one end thereof, which cam engages an arm 130 integral with the cam follower 121. At the end opposite the cam 129, the plunger 127 has an enlarged head 131 comprising a pair of locked nuts threaded thereon. A spring 132 is coiled about the plunger 1'27 and acts between the head 131 and the bearing lug 55 to urge the plunger 127 to the right as seen in FIG. 3, which action causes the cam 129 at the end thereof to force the arm 130 downwardly and thereby lift the follower 121 from the surface of the cam 116. As the follower 57 is moved into its extreme position at the left in FIG. 3, the head 131 of the plunger 127 is engaged by an arm 133 integral with the follower 57 and moved to the left against the action of the spring 132. As the cam 129 is moved to the left, the follower 121 is permitted to fall into contact with the cam 116, thus rotating the hub thereof to align the slots 125 with the tongues 126 permitting mating of the same to key the follower 121 to the shaft 54. When in this positionthe selector lea/er 74 is adapted to be seated in a special slot 134 (FIG. 4) in the cover plate 77, and the follower 57 is free of the cams 63 so that it will merely idle in space instead of ride on one of the cams 63, thus preventing unnecessary wear. Since the selector lever 74, when in the slot 134, must hold the plunger 127 depressed against the action of the spring 132, there has been provided a means to assist in this function, which means comprises a slot 135 (see FIG. 1) formed in an enlargement 1360f the ridge 84 on the cover plate 5, which slot is entered by the arm 133 (FIG. 3).

Referring again to FIG. 8, the bell-crank 29 and the carrier 26, which is mounted on the bell-crank 29, are pivoted on the needle-position control shaft 30. The pivotal movement of these elements is therefore about the axis of the shaft 30. The stud 43 is mounted eccentrically upon the end of shaft 30 and it extends into the slot 44 in the carrier 26 which is oscillating about the axis of the shaft 30. Consequently, during normal operation, the oscillation of the carrier 26 will be imparted through the lugs 45 and stud 43 to the shaft 30, thereby vibrating the control knob 46. In FIG. 12, there is illustrated a modification of the needle-position control mechanism wherein the knob 46 will not be oscillated.

With reference to FIG. 12, the needle-position control shaft 30a extends only through the bearing 137 at the rear of the standard 2a. A collar 138 is secured on the end of the shaft 30a to prevent axial displacement thereof. The control knob 46a is mounted upon a shaft 139 journaled in a bore in a bushing 140 fitted into the front wall of the standard 2a and held by screws 141. The bore in the bushing 140 to receive the shaft 139 is enlarged at the inner end 14 2 and at the intersection of the two differently diametered portions of the bore there is formed a shoulder 143. The inner end of the shaft 139 is reduced as at 144 and at the intersection of the two differently diameted sections of the shaft, there is provided a flange that is adapted to abut against the shoulder 143. A spring 146 is disposed in the annular space between the enlarged inner end 142 in the bore in the bushing 140 and the reduced end 144 of the shaft 139. The spring 146 acts to urge the shaft 139 to the left in FIG. 12 to the stop position in which the flange 145 abut against the shoulder 143. At its other end, the spring 146 acts against a plate 147 secured to the bushing 140' by screws 148.

The shaft 139 is axially aligned with the shaft 30a and is longitudinally'slidable against the action of the spring 146 toward the end of the shaft 3%. At their adjacent ends, the shaft 139 is provided with a tongue 149 and the shaft 30a is provided with a mating groove 150. In order to effect an adjustment of the needle-position control mechanism, which adjusment is accomplished by rotation of the shaft 30a, the finger knob 46a is depressed. This urges the tongue 149 into the groove 150 and couples the shafts 30a and 139 together for rotation. When released, the spring 146 will uncouple the shafts 30a and 139 so that the oscillation of the shaft 30a during operation of the machine will not be transmitted to the shaft 139.

To indicate the setting of the n edle-position control mechanism, there is provided an indicator 151 surrounding a sleeve-like reduced end 152 of the b aring 140 and having a pointer 153 that cooperates with an indicia plate 154 on the standard 2a. The indicator 151 is held on the reduced end 152 by a retaining ring 155 and is frictionally held against movement by a spring washer 156 disposed between the retaining ring 155 and indicator 151 to urge the indicator against the end of tlte bearing 140. A pair of cars 157 are struck from the indicator 151 and the knob 46a is provided with an arm 158 extending into the space between the ears 157 when the knob is pushed in to key the shaft 139 to the shaft 30a through the tongue and groove 149 and 150 whereby rotation of the knob 46a will effect rotation of the indicator 151.

In FIGS. 13 through 21, there is illustrated a modified form of the invention. In this modified form of the invention there is illustrated a sewing machine having a frame including a standard 20 carrying a bracket-arm 3a. A main shaft 6a (FIG. 16) is journaled longitudinally of the bracket-arm and has mounted thereon within the bracket arm a sleeve 159 carrying a stack 120a of pattern cams 63a keyed to the sleeve 159 by a key 100a, the cams 63a being held on the sleeve 159 by a nut 99a threaded onto the sleeve and compressing the cams against a flange 160 on the sleeve. The sleeve 159 is journaled at its ends in bearing bosses 161 and 162 having removable caps 163 and 164, respectively, secured to the bosses by screws 165, FIGS. 19 and 20. The stack 120a of cams is mounted on the machine by placing it in position on the bearing bosses 161 and 162 and securing them in place by the caps 163 and 164, and thereafter inserting the main shaft 6a through the bore of the sleeve 159.

The sleeve 159 is held against axial sliding by the flange 160 and by the hub of a gear 166 secured on the sleeve, which elements engage the opposite faces of the bearing boss 162. The sleeve 159 is rotated relatively to the shaft 6a by means of a reduction drive including the gear 166. The gear 166 meshes with a gear 167 mounted on a countershaft 168 journaled in the bracket arm 3a parallel to the main shaft 6a. The countershaft 168 carries a gear 169, FIG. 21, meshing with a gear 170 on a second countershaft 171 journaled in the bracket arm 3a with its axis normal to the axis of the main shaft 6a. The countershaft 171 in turn carries a worm wheel 172 meshing with a worm 173 on the main shaft.

Aside from having the pattern cams mounted upon the main shaft 60, a modified form of the cam follower mechanism is illustrated in the embodiment of FIGS. 13 21. This modified cam follower mechanism comprises a pivot shaft 54a journaled longitudinally of the bracket arm 3a Mounted on the pivot shaft 54a is a first cam follower 57a and two additional cam followers 174 and 175, each of which are slidable axially on the pivot shaft 54a but keyed thereto for rotation. The follower 57a has a selector lever 74a with a finger-piece 79a to provide for manually shifting the follower into contact with a selected one of the cams 63a, and a pointer 80a that cooperates with suitable indicia on a cover plate 176 for indicating the selected cam. The cam follower 174 has a selector lever 177 with a finger-piece 178 and a pointer 179 while the cam follower has a selector lever 180 with a finger-piece 181 and a pointer 182. The finger-pieces 79a, 17-8 and 181 are respectively identified by the numerals A, B and C, as indicated in FIG. 14 to identify the respective followers. To position the followers or any one of them on the cams, there is a slotted cover plate 77a through which the selector levers extend, which plate has slots S-1a corresponding to one of the cams 63a. In operation, the finger-piece 79a is used to shift the corresponding cam follower onto a selected one of the cams 63a. When so positioned, the pivot shaft 54a will be oscillated in accordance with the pattern of the selected one of the cams 63a. In the same manner as in the embodiment of invention set forth in FIGS. 1-11, oscillation of the pivot shaft 54a is transmitted through a crank arm 53a, universal link 52a, and arm 35a to the 'bell-crank 29a which is pivotally mounted on the needleposition control shaft 30a, and then through the car- 9 V rier 26a and the pitman 19 to the needle-bar mechanism. The needle-position is controlled by the shaft 30a which is manually set by means of the control knob 46a, and the lateral vibration of the needle-bar is controlled by the control knob 4 1a on the end of the shaft 40a having the crank arm 39a that varies the position or point of connection of the end of the pitman 19a with relation to the carrier 26a.

The three extreme left positions of the cam followers,

as seen in FIG. 14, are not provided with pattern cams. Thus, when the cam followers are set as indicated in full lines in FIGS. 14 and 15, only the follower 57a will be operative to impart a pattern of vibration to the pivot shaft 54a. When the follower 57a is moved into its extreme left position as indicated in dotted lines in FIG. 15, none of the followers will be in operative relation with a pattern cam so that there will be no vibration imparted to the pivot shaft 54a, or in other words, the machine will sew in a straight line. As indicated in FIG. 15, the followers 174 and 175 are offset to provide for placing the same upon three adjacent cams.

, When desired, either or both of the followers 174 and 175 may be brought into operative relation with one of the cams 63a in conjunction with the follower 57a so that the resulting oscillation imparted to the pivot shaft 54a'will be a combination of the patterns of the selected cams, thus multiplying the number of possible stitch patterns beyond the number of cams employed. In addition, each of the individual cam followers may be positioned to ride on two adjacent ones of the cams 63a, thus further multiplying the available number of stitch patterns. Toward this end, the cover plate 77a is secured to the bracket arm cover plate a by screws 78a which extend through elongated apertures 183 in the plate 77a.. Thus theplate77a can be shifted laterally so that the slots 81a will be located astride two adjacent cams rather than directly opposite one cam.

- Numerous alterations of the structure herein disclosed will suggest themselves to those skilled in the art. However, it is to be understood that the present disclosure relates to a preferred embodiment of my invention which is for purposesofi illustration only and not'to be construed as a limitation of the invention. All such modifications which do not depart from the spirit of the invention are intended to be included within the scope of the appended claims. W

-Having thus described the nature of the invention, what I claim herein is:

1. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main shaft and said needle bar for imparting endwise reciprocation to the needle-bar upon rotation of said shaft, a pitman operatively connected to said needle bar for imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of said sewing machine comprising a plurality of axially aligned stitch-pattern cams rotatably carried by said frame with the axis thereof extending in the same direction as the axis of said main shaft, drive connections between said' mainshaft and said cams for rotating said cams upon rotation of said main shaft, a pivot shaft journaled in said frame on an axis parallel to the axis of said main shaft, a plurality of separate cam follower elements independently mounted on and slidable along said pivot shaft for operatively engaging each of said cam follower elements with a selected one of said cams, said cam followers being keyed to said pivot shaft for unitary turning, means for biasing said cam followers into operative engagement with selected ones of said cams, said cams imparting a pattern of oscillation to said cam fol- 10 lowers and to said pivot shaft upon rotation of said cams, and operative connections between said pivot shaft and said pitman for actuating said pitman upon actuation of said pivot shaft.

12. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main-shaft and said needle bar for imparting endwise reciprocation to said needle-barupon rotation of said shaft, a pitman operatively connected to said needle-bar for imparting vibration thereto upon actuation of said pitman, and means for actuating sa-id pitman during operation of the sewing machine comprising a plurality of axially aligned stitch-pattern main shaft rotatably carried by said frame on an axis parallel to the axis of said cams, drive connections between said main shaft and said cams for rotating said cams upon rotation of said main shaft, a pivot shaft journaled in said frame on an axis parallel to the axis of said cams, a plurality of separate cam followers individually slidable alongand keyed to said pivot shaft, selector means for individually sliding said cam followers along said pivot shaft, means for biasing said cam followers into operative engagement with the periphery of selected ones of said cams, said cams imparting a pattern of oscillation to said cam followers and to said pivot shaft upon rotation of said cams, and operative connections between said pivot shaft and said pitman for actuating said pitman uponoscillation of said pivot shaft. 7

3. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main shaft and said needle-bar for imparting endwise reciprocation to the needle-bar upon rotation of said shaft, a pitman operatively connected to said needle-bar for imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of said sewing machine comprising a plurality of axially aligned stitch-pattern cams rotatably carried by said frame with, the axis thereof extending in the same direction as the axis of said main. shaft, drive connections between said main shaft and said camsfor rotating said cams upon rotation of said main-shaft, a pivot shaft journaled in said frame onan axis parallel to the axis of said main shaft, a cam follower slidably mounted on said pivot shaft for movement relatively to said cams and keyed to said pivot shaft for unitary turning, means for selectively moving said cam follower into operative engagement with a selected one of said cams or 'with two adjacent cams, and operative connections between said pivot shaft and said pitman for actuating said pitman upon actuation of said pivot shaft.

4. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main'shaft journaled in said frame for rotation, operative connections between said main-shaft and said needle-bar for imparting endwise reciprocation to said needle-bar upon rotation of said shaft, a pitman operatively connected to said needle-bar for imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of the sewing machine comprising a plurality of axially aligned stitch-pattern cams rotatably carried by said frame with the axis thereof extending in the same direction as the axis of the main shaft, drive connections between said main shaft and said cams for rotating said cams upon rotation of said main shaft, a pivot shaft journaled in said frame on an axis parallel to the axis of said cams, a cam follower slidable along and keyed to said pivot shaft, means for biasing said cam followers into operative engagement with the periphery of said earns, selector means for sliding said cam follower along said pivot shaft, a plate having positioning means for locating said selector means and for releasably holding said selector means in the set position, means for adjustably securing said plate to said frame, said plate being adjustable between a position in which said positioning means is located to place said cam follower in operative engagement with the periphery of a selected one of said cams and a position in which it is located to place said cam follower in operative engagement with the periphery of two adjacent ones of said cams, said cams imparting a pattern of oscillation to said cam follower and said pivot shaft upon rotation of said cams, and operative connections between said pivot shaft and said pitman for actuating said pitman upon oscillation of said pivot shaft.

5. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main shaft and said needle-bar for imparting endwise reciprocation to said needle-bar upon rotation of said shaft, a pitman operatively connected to said needle-bar for imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of said sewing machine comprising a drive shaft journaled for rotation in said frame and arranged parallel to said main shaft, drive connections between said main shaft and said drive shaft for rotating said drive shaft upon rotation of said main shaft, a cam-supporting shaft arranged in axial alignment with said drive shaft, means for rotatably supporting one end of said cam-supporting shaft and for keying the cam-supporting shaft to said drive shaft for unitary rotation, said supporting means being releasable upon endwise shifting of said cam-supporting shaft relative to said drive-shaft, endwise shiftable means for rotatably supporting the other end of said camsupporting shaft, a plurality of stitch-pattern cams carried by said cam-supporting shaft, cam follower means selectively engageable with said cams, and operative connections between said cam-follower means and said pitman for actuating said pitman upon rotation of said cams.

6. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main shaft and said needle-bar for imparting endwise reciprocation to said needle-bar upon rotation of said shaft, a

pitman operatively connected to said needle-bar for t imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of said sewing machine comprising a drive shaft journaled for rotation in said frame and arranged parallel to said main shaft, drive connections between said main shaft and said drive shaft for rotating said drive shaft upon rotation of said main shaft, a cam-supporting shaft arranged in axial alignment with said drive shaft, means for rotatably supporting one end of said cam-supporting shaft and for keying the cam-supporting shaft to said drive shaft for unitary rotation and said means being releasable upon endwise shifting of said cam-supporting shaft relative to said drive shaft, an endwise-shiftable shaft journaled for rotation in said frame and arranged in axial alignment with said cam-supporting shaft on the end opposite from said drive shaft, cooperating means formed in the adja= cent ends of the endwise-shiftable shaft and the camsupporting shaft for supporting the end of said camsupporting shaft and for keying the two together, releasable means for normally locking the endwise-shiftable shaft against endwise motion, a plurality of cams carried by said cam-supporting shaft, a special cam releasably mounted upon the free end of said endwise shiftable shaft, cam follower means selectively engageable with said cams, and operative connections between said cam follower means and said pitman for actuating said pitman upon rotation of said cams.

7. In a sewing machine having a frame, a needle-bar mounted in said frame for lateral oscillation and for endwise reciprocation, a main shaft journaled in said frame for rotation, operative connections between said main shaft and said needle-bar for imparting endwise reciprocation to said needle-bar upon rotation of said shaft, 9. pitman operatively connected to said needle-bar for imparting vibration thereto upon actuation of said pitman, and means for actuating said pitman during operation of said sewing machine comprising a cam shaft journaled for rotation in said frame and arranged parallel to said main shaft, drive connections between said main shaft and said cam shaft for rotating said cam shaft upon rotation of said main shaft, a plurality of cams carried by said cam shaft and a special cam carried by said cam shaft and spaced from said plurality of cams, a pivot shaft arranged parallel to said main shaft, a first earn follower slidable along but keyed to said pivot shaft and biased into operative engagement with the periphery of a selected one of said cams, a second cam follower arranged on said pivot shaft to operatively engage said special cam, means for keying said second cam follower to said pivot shaft when said first cam follower is in a predetermined position, means controlled by the position of said first cam means for lifting said second cam follower from the periphery of said special cam when said first cam follower is moved from the predetermined position, said cam followers effecting a selected pattern of oscillation of said pivot shaft upon rotation of said cams, and operative connections between said pivot shaft and said pitman for actuating said pitman upon oscillation of said pivot shaft.

References Cited by the Examiner UNITED STATES PATENTS 2,682,845 7/1954 Casas Robert et al. 112-158 2,684,649 7/1954 Scarpa 112158 2,693,778 11/1954 Harris 112158 2,713,838 7/1955 Johnson et al. 112-1S8 2,832,302 4/1958 Gegauf 112158 2,862,468 12/1958 Johnson 112-158 FOREIGN PATENTS 784,689 5/1935 France.

1,095,914 12/1954 France.

19,184 1908 Great Britain.

JORDAN FRANKLIN, Primary Examiner.

THOMAS J. HICKEY, DAVID J. WILLIAMOWSKY,

Examiners. G, A, MYSLIWIEC, H. D. COOPER,

Assistant Examiners. 

1. IN A SEWING MACHINE HAVING A FRAME, A NEEDLE-BAR MOUNTED IN SAID FRAME FOR LATERAL OSCILLATION AND FOR ENDWISE RECIPROCATION, A MAIN SHAFT JOURNALED IN SAID FRAME FOR ROTATION, OPERATIVE CONNECTIONS BETWEEN SAID MAIN SHAFT AND SAID NEEDLE-BAR FOR IMPARTING ENDWISE RECIPROCATTION TO THE NEEDLE-BAR UPON ROTATION OF SAID SHAFT, A PITMAN OPERATIVELY CONNECTED TO SAID NEEDLE BAR FOR IMPARTING VIBRATION THERETO UPON ACTUATION OF SAID PITMAN, AND MEANS FOR ACTUATING SAID PITMAN DURING OPERATION OF SAID SEWING MACHINE COMPRISING A PLURALITY OF AXIALLY ALIGNED STITCH-PATTERN CAMS ROTATABLY CARRIED BY SAID FRAME WITH THE AXIS THEREOF EXTENDING IN THE SAME DIRECTION AS THE AXIS OF SAID MAIN SHAFT, DRIVE CONNECTIONS BETWEEN SAID MAIN SHAFT AND SAID CAMS FOR ROTATING SAID CAMS UPON ROTATION OF SAID MAIN SHAFT, A PIVOT SHAFT 